Remote Sensing data

Objectives

Remote sensing Introduction

Active Earth Observing Satellites (EOS) (as of 8/31/2015)

From the Union of Concerned Scientists Satellite Database and Pixalytics Blog

Debris & Satellites in low Earth orbit

Image courtesy of European Space Agency

NASA’s Earth Observing System

Passive Remote Sensing

Electromagnetic Radiation

EarthData.nasa.gov

Datasets, news, articles, information

EarthData.nasa.gov

Datasets, news, articles, information

MODIS

Moderate Resolution Imaging Spectroradiometer (MODIS)

2 Satellites Terra launched in 1999, Aqua in 2002.

Technical Details: swath

Viewing swath width of 2,330 km

Technical Details: spatial coverage

Covers Earth every one to two days

Technical Details: spectral coverage

36 spectral bands between 0.405 and 14.385 µm

Technical Details: spatial resolution

3 spatial resolutions – 250m, 500m, and 1,000m

MODIS Data Processing

MODIS products (a subset…)

Atmosphere

Cryosphere Products

Ocean Products

Land Products

Example product workflow

MODIS Products used to generate vegetation indices. From the MOD13 Algorithm Theoretical Basis Document.

Data formats

Most NASA EOS data distributed as HDF files, which are very similar to netCDF.

NetCDF / HDF

Collection-Level Naming Conventsions

MODIS/Terra Surface Reflectance 8-Day L3 Global 500m SIN Grid V005

MODIS Gridding system

Filename Conventions

MOD09A1.A2006001.h08v05.005.2006012234657.hdf

MODIS Temporal Resolution

MODIS Spatial Resolution

MODIS Data

Distributed Active Archive Centers (DAACs)

Accessing data

The Land Processes Distributed Active Archive Center has a nice “Data Discovery” Tool:

MODIS Products Table

Lists all available MODIS land products

Annual Land Cover Type Description

Detailed layer information

Downloading: http/ftp access

or the LP DAAC2Disk Download Manager which builds a download script.

MODIS Reprojection Tool

Available at lpdaac.usgs.gov/tools/modis_reprojection_tool.

MODIS Reprojection Tool: Subset & Reproject

MCD12Q1.A2012001.h12v04.051.2014288200441.hdf

MODIS Web Services

daacmodis.ornl.gov/cgi-bin/MODIS/GLBVIZ_1_Glb/modis_subset_order_global_col5.pl

MODIS Subset: Spatial

MODIS Subset: Variables

MODIS Subset: Temporal

Submit email and wait for results…

MODIS Subset: Results & Download

MODIS Subsets: API

Subsets of MODIS Land Products through Simple Object Access Protocol (SOAP).

MODISTools R package.

Presentation Credits